Low voltage bus for an appliance

ABSTRACT

According to an aspect of the present invention a control system for an appliance includes a plurality of peripheral devices and a plurality of sensors and a controller. A first communications/DC power bus is coupled to the plurality of sensors and peripheral devices and coupled to the controller. A second communications/ac power bus is coupled to the plurality of sensors and peripheral devices and coupled to the controller. Wherein the controller is configured to receive data from the sensors over the either communications bus and transmit control operations to the peripheral devices based on the data.

BACKGROUND OF THE INVENTION

This invention relates generally to control systems for appliances, and more particularly, to a control system for a refrigerator.

Known household appliances are available in various platforms having different structural features, operational features, and controls. For example, known refrigerator platforms include side-by-side single and double fresh food and freezer compartments, and vertically oriented fresh food and freezer compartments including top mounted freezer compartments, and bottom mounted freezer compartments. Conventionally, a different control system may be used in each refrigerator platform. For example, a control system for a side-by-side refrigerator typically controls the freezer temperature by controlling operation of a compressor and controls the fresh food compartment through the operation of a mullion damper located between the fresh food compartment and the freezer compartment, a fresh food fan and a variable or multi-speed fan-speed evaporator fan. Top mount refrigerators and bottom mount refrigerators however, are available with and without a mullion damper, the absence or presence of which consequently affects the refrigerator controls.

Other major appliances, including dishwashers, washing machines, dryers and ranges, are available in various platforms and employ different control schemes.

Known electronically controlled appliances typically employ a dedicated connection between a controller and a plurality of peripheral devices, including but not limited to sensors to monitor various operating conditions of the appliance. Typically, analog signals are transmitted between the sensors and the controller. These analog signals, however, are vulnerable to electrical interference, which can compromise performance of the appliance. To reduce electrical interference, additional electronic circuitry may be employed, but only at increased complexity and cost of the control scheme. Further, ever-expanding appliance features entail relatively sophisticated control schemes and many electrical connections to place all the peripheral devices in communication with the controller. A large number of electrical connections not only increases assembly costs, but presents a possible defect in manufacturing or possibility of failure in use.

BRIEF SUMMARY OF THE INVENTION

According to an aspect of the present invention a control system for an appliance includes a plurality of peripheral devices, a plurality of sensors and a controller. A first communications/DC power bus is coupled to the plurality of sensors and peripheral devices and coupled to the controller. A second communications/AC power bus is coupled to the plurality of sensors and peripheral devices and coupled to the controller. Wherein the controller is configured to receive data from the sensors over either communications bus and transmit control operations to the peripheral devices based on the data.

According to another aspect of the present invention a refrigerator comprises a control system for an appliance which includes a plurality of peripheral devices, a plurality of sensors and a controller. A first communications bus provides DC power to peripheral devices and is coupled to the plurality of sensors and coupled to the controller. A second communications bus provides AC power to peripheral devices and is coupled to the plurality of of sensors and peripheral devices and coupled to the controller. Wherein the controller is configured to receive data from the sensors over a communications bus and transmit control operations to the peripheral devices based on the data.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a refrigerator.

FIG. 2 is a perspective view of the refrigerator of FIG. 1 with the doors in a open position.

FIG. 3 is a block diagram of a distributed low voltage bus system of the refrigerator of FIG. 1 according to an aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION

It is contemplated that the teaching of the description set forth below is applicable to all types of appliances, including but not limited to refrigerators but include a standalone refrigeration unit or may be connected to ranges, microwaves, and other appliances. The present invention is therefore not intended to be limited to any particular refrigeration device or configuration of cooling circuit 100 for the temperature controlled medium.

FIGS. 1 and 2 illustrate a side-by-side refrigerator 100 including a fresh food compartment 102 and freezer compartment 104. Freezer compartment 104 and fresh food compartment 102 are arranged in a bottom mount configuration where the freezer compartment 104 is below the fresh food compartment 102. The fresh food compartment is shown with French opening doors 134 and 135. However, a single door may be used. Door or drawer 132 closes freezer compartment 104.

The fresh food compartment 102 and freezer compartment 104 are contained within an outer case 106. As shown in FIG. 2, Mullion 114 separates the fresh food compartment 102 and the freezer compartment 104.

Door 132 and doors 134, 135 close access openings to freezer and fresh food compartments 104, 102, respectively. Each door 134 and 135 is mounted by a top hinge 136 and a bottom hinge 137 to rotate about its outer vertically oriented edge between an open position, as shown in FIG. 2, and a closed position shown in FIG. 1 closing the associated storage compartment.

In accordance with known refrigerators, refrigerator 100 also includes a machinery compartment (not shown) that at least partially contains components for executing a known vapor compression cycle for cooling air in the compartments. The components include a compressor, a condenser (not shown), an expansion device (not shown), and an evaporator (not shown) connected in series and charged with a refrigerant. The evaporator is a type of heat exchanger that transfers heat from air passing over the evaporator to a refrigerant flowing through the evaporator, thereby causing the refrigerant to vaporize. The cooled air is used to refrigerate one or more fresh food or freezer compartments via fans (shown schematically in FIG. 3 as 534). Collectively, the vapor compression cycle components in a refrigeration circuit, associated fans, and associated compartments are referred to herein as a sealed system. The construction of the sealed system is well known and therefore not described in detail herein, and the sealed system is operable to force cold air through the refrigerator 100.

FIG. 3 illustrates an exemplary low voltage bus system 500 with controller 502 in accordance with one embodiment of the present invention. Controller 502 can be used, for example, in refrigerators, freezers and combinations thereof, including but not limited to refrigerator 100 (shown in FIGS. 1 and 2). It is recognized, however, that controller 502 is easily adaptable to control other types of appliances, including but not limited to dishwashers, washing machines, dryers and ranges in light of the principles set forth below.

Controller 502 includes a diagnostic port 562 and a human machine interface (HMI) board 564 coupled to a main control board 566 by an interprocessor communications bus 568. HMI board 564 is coupled to a HMI display device 200, which may include a touch screen or other input as well as a liquid crystal display for outputting features and parameters to a user. It should be realized that HMI display device may be any user input such as buttons, switches, keyboard or mouse as well as the above mentioned touch screen or any other input means. Additionally, the output feature may be any output means including the above referenced LCD screen as well as, light emitting diode signals, or any other known display means.

Main control board 566, human machine interface (HMI) board 564 are coupled to a power supply 632 which receives an AC power from a protection unit 634. Protection unit 634 may sense and protect the unit from current leakage or arcing using ground fault or arc fault technology. The protection unit may communicate with and/or be controlled by the main control board 566. The input voltage may be 90-265 Volts AC, 50/60 Hz signal.

Main control board 566 monitors and manages the DC input and output bus 520 and the AC input and output bus 540 as well as power supply current and voltage, brownout detection, compressor cycle adjustment, analog time and delay inputs where the analog input is coupled to an auxiliary device such as a clock or finger pressure activated switch, analog pressure sensing of the compressor sealed system for diagnostics and power/energy optimization. Further input functions include external communication via power line, infrared detectors or sound detectors, human machine interface display dimming based on ambient light, adjustment of the refrigerator to react to food loading and changing the air flow/pressure accordingly to ensure food load cooling or heating as desired, and altitude adjustment to ensure even food load cooling and enhance pull-down rate of various altitudes by changing fan speed and varying air flow.

A plurality of digital inputs 522, 524, 526, 528, 530, 532, 534, 536 and 538 (collectively 522-538) are disclosed in FIG. 3. Digital devices 522-538 correspond to, but are not limited to, a condenser fan speed, an evaporator fan speed, a door detector 198, dispenser ice chute obstruction detection, light emitting diodes and various thermisters. These devices may function as inputs or outputs to the microprocessor and may draw DC power from the bus 520.

Main control board 566 also is coupled to an AC input/output bus 540 for managing various AC peripheral devices 542-548. AC input/output bus 540 may be separately wired (not shown) or sent over the conditioned power supply wires, as shown. AC peripheral devices 542-548 may include but are not limited to a crusher solenoid, an auger motor, a water dispenser valve, a compressor control, a defrost heater, the operating speed of a variable speed condenser fan, a fresh food compartment fan, an evaporator fan, and a quick chill system feature pan fan.

Each of the DC peripheral devices 522-538 and AC peripheral device outputs 542-548 are assigned a unique address by the main control board 566. By utilizing information from each of the inputs 522-538 the main control board 566 may manipulate the various peripheral devices 542-548 or 522-538. Manipulation may include safety shutoff of various features, energy efficient operation, and lighting or other human interface programming and control or other features or controls required by the particular application.

While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. 

1. A control system for an appliance including a plurality of peripheral devices and a plurality of sensors, the control system comprising: a controller; a first communications/DC power bus coupled to the plurality of sensors, or peripheral devices and coupled to the controller; and a second communications/AC power bus coupled to the plurality of sensors, or peripheral devices and coupled to the controller; wherein the controller is configured to: receive data from the sensors over either communications bus; and transmit control operations to the peripheral devices based on the data.
 2. A control system for an appliance according to claim 1, wherein said communications bus comprises a serial communications bus.
 3. A control system for an appliance according to claim 1, further comprising a human machine interface board, the human machine interface board coupled to a human machine interface.
 4. A control system for an appliance according to claim 3, wherein the human machine interface comprising a touch screen device.
 5. A control system for an appliance according to claim 1, further comprising a power-conditioning device.
 6. A control system for an appliance according to claim 1, wherein the plurality of peripheral devices comprises a variable speed compressor of a vapor compression circuit.
 7. A control system for an appliance according to claim 1, wherein the plurality of peripheral device comprises variable speed fans configured to move air past an evaporator to cool a compartment.
 8. A control system for an appliance according to claim 1, further comprising a diagnostic communications port and a collision detection system.
 9. A control system for an appliance according to claim 1, wherein the serial communications bus comprises an asynchronous serial communications bus.
 10. A control system for an appliance according to claim 1, wherein the plurality of devices includes an icemaker.
 11. A control system for an appliance according to claim 1, wherein said plurality of sensors and peripheral devices are each configured to be assigned a unique address.
 12. A refrigerator comprising a control system for a plurality of peripheral devices, said control system comprising: a controller; a first communications/DC power bus coupled to the plurality of sensors, or peripheral devices and coupled to the controller; and a second communications/AC power bus coupled to the plurality of sensors, or peripheral devices and coupled to the controller; wherein the controller is configured to: receive data from the sensors over either communications bus; and transmit control operations to the peripheral devices based on the data.
 13. A refrigerator according to claim 12, wherein said communications bus comprises a serial communications bus.
 14. A refrigerator according to claim 12, further comprising a human machine interface board, the human machine interface board coupled to a human machine interface.
 15. A refrigerator according to claim 14, wherein the human machine interface comprising a touch screen device.
 16. A refrigerator according to claim 12, further comprising a power-conditioning device.
 17. A refrigerator according to claim 12, wherein the plurality of peripheral devices comprises a variable speed compressor of a vapor compression circuit.
 18. A refrigerator according to claim 12, wherein the plurality of peripheral device comprises variable speed fans configured to move air past an evaporator to cool a compartment.
 19. A refrigerator according to claim 12, further comprising a diagnostic communications port and a collision detection system.
 20. A refrigerator according to claim 12, wherein the serial communications bus comprises an asynchronous serial communications bus.
 21. A refrigerator according to claim 12, wherein the plurality of devices includes an icemaker.
 22. A refrigerator according to claim 12, wherein said plurality of peripheral devices are each configured to be assigned a unique address. 